Photographic flash-bulb socket



oct. 18, 1949.

G. PRAGER PHOTOGRAPHIC FLASH-BULB SOCKET Filed Dec. l, 1948 m G A l P Y v mi 5 0 uw s.

V.. Du LMI 55 ATTORNEYS Patented Oct. 18, 1949 LJN-treo STATES PATE-Nr oFF-ICE;

PHOTOGRAPHIG FLASH-BULB SOCKET Gustav Prager, New York,.N. Application-December 1, 1948,--S'erial No1-62,889Y

6Claims. l

My' invention relates tor sockets for" retaining photographic flashlight'bulbs', andfhas particularreference to a socket ywhichis adapted tohold flash bulbs off various sizes-and to leject the used bulb immediately after ignition;

Thereware flash-bulb lioldersinruse` today in which provision is.l` made tof-eject a used bulb without-requiring :the user'to'touch ,the hot bulb with his ingersfv These holdersare, however, adapted to hold a buibof alsingle size only.vv Since flasl'ibulbs are nowv manufactured in a variety of sizes;- eaoh'of the `various sizesxhaving a' diameterl of aidiife'rentlsize; `it would' be desirable-to provide `'af-flash#bulb-socket :which would'not only retain; ar` bulb' of anyA basez diameter, but which wouldejectthebulb after ignition.4 1

Ity is the principali objectf of my invention, therefore; to provide a vflash-bulb socket which will retain bulbs-having Vbase diameters-of varyingsizes.

Anotherf object'of my'- invention is `the provision of a sockety for flash bulbs.; ofthe character described which is providedvw-itli meansforeiciently ej ectin'g ausedbulb:-

Stillanother' object of: my invention is the provision of a fiashdbulb socket-whichis simple and Aconvenient toioperate, and-which will securely retain -thef-bulb in a locked position.

These and otherobjectsofmy invention'will be readily lapparent thecourse lof the fol'lowf ign specification,.when .taken connection with theacoompanying 'drawingspin which:

Fig. l is a frontelevaton `of myejectorsocket, with .the movablerrretaining Aarmsfshow-n :in their innermost closed position; `the guide-grooves be- 3;

ing .shownvin broken lines; lanchaI portion -1 of the base beingz :broken away-'to reveal ,the electric Soutlet contained therein.

Fig. 2 is asectionalyiew t-aken'alonglinel--Z of Fig. 1, .portions thereof, suchzas. the plunger head being1 shown inperspective forrclarity-of illustration.

Fig.y 3 is a front elevation `similarA tQFig. 1, but

' with the retainingI armsshownxin their lextreme openposition,v and-...with Ia portion ofthe socket being broken away to disclosesthezninnerr construction thereof.

Fig- Liis a sectional view taken 'along' line Ile-4 of Fig. 1, with the-ejector-so-clretbeingfwhollyl depressedpand withtheoentireplunger arrn`being 1.

cylinders are. secured to each other; withrtheir ed at its lower periphery, .as Aat I2, to enable the longitudinal axes -disposed -at right angles to each other. Both of theY aforementioned cylinders land their. associated parts are constructedlof ya conductive; material; preferably a lightA metal, with: ther exception'of certain insulated parts Whichzareiindicated in thedrawingswith heavy shade :lines and which will hereinafter be identied. The base cylinder I-I is externally thread- `tofby aplurality of clamping screws I6. The

lower portion of the. peripheral flange I5 acts as a stop to preventthe base wal1 or plate =I4 from being. thrust oripushed into'ther'socket cylinder Il).

Asshown'in Figs. 2 and 4, a disc I'I is turnably mounted beneath the base wall M, the outer marginal edge of said disc II abutting the lower portion of peripheral iiange` I5r andbeing held in place thereby. A peripheral flange I8, integral with disc I"I`,acts` asa, ngerzpiece by which the said disc may; be manually rotated in either direction. The saiddisc member I'I is held in place from below bya circular plate I9, which plate also serves as the lower-most wall of the socket cylinder unit. Thesaid vplate I9-has a'raised inner circular portion or boss 20 uponwhich said disc Il is set and around which thesaid disc I'l turns. Circular plate I9 is secured to the base wall I4 by meansopthe elongated screws 2| which extend througlrithe raised portion or lboss 2i] of said circular plate I9.

Base Wall I4 is provided with four curved, radially-extending slots 2 which :are disposed around the face of said base wall in equallyspaced relation to each other. Rotatable disc I'I .is alsofprovided with an equal number of straight,

equally-#spaced slots 23 which are substantially longer than slots 22. As shown in Figs. 1 and 3, slots 231are arranged with one end adjacent the circumferential edge of disc I1, the other end of each of said slots-extending in a clockwise direction at an acute Vangle toward the center of said disc I'l. Each of slots 22 of base wall I4 :are so located as to register with one of the slots of disc I'I. when disc` i1 is in operative position. x ,Assliown in Figs:v l and 2, slot'23 registers with the bottom of slot 22 (Fig. 1) and then travels upward along slot 22 as disc |1 is rotated in a clockwise direction, until it registers with the top f slot 22 (Fig. 3). As will be presently shown, this movement is important in the operation of the retaining elements of the socket.

Four flat, arcuate movable yarms 24 are pivotally connected to the top face of base wall I4, in parallel yadjacent relation thereto by means of rivets 25. Each said arm 24 carries a centrally-located, depending pin or lug 26 which extends through one of the slots 22 and partially through the respective registering slot 23. Each said arm 25 yalso carries a retaining arm '21. These retaining arms 21 are made of a double thickness of metal as shown -in Fig. 2, said metal being a springy vand resilient material. arms 21 comprise an integral horizontal |bottom flange 28 and an outwardly flared or tapering upper end or lip 29. The bottom flange 28 is attached to the movable arm 24 by means of rivets 29a or by any other suitable means of attachment, such as soldering, welding, or the like. The flared or tapered upper ends 29 facilitate the insertion of bulbs between the retaining arms 21, and also the ejection of the bulb therefrom.

Since the pins or lugs 26 extend through slots 22 and into slots 23, it is evident that when the disc I1 is rotated clockwise, causing the slot 23 to move from register with the lower end of slot o 22 to the upper end of slot 22, the pin 26 will also be carried upward in unison therewith within slot 22. This movement of pin 26 is caused by a cam action which is exerted by the inner wall of slot 23 upon said pin. When said disc I1 is rotated in a counter-clockwise direction, pin 26 will travel from the outer end of slot 22 to the inner end thereof. This latter position is illustrated in Fig. 3.

The pins 26 being attached to movable arms 24, the said arms 24 will pivot upon the rivets 25 when said pins 2B are moved by rotation of disc I1 as was previously described. Thus rotation of disc I1 will cause the retaining arms 21 to move between their positions adjacent the center of the socket cylinder I0 (Fig. 1) and adjacent the circumference thereof (Fig. 3). l

Means for ejecting a hot bulb is afforded by the provision of a plunger mechanism designated generally by reference numeral 30. Said plunger mechanism is attached to the outside of the socket cylinder l0 and extends through the circular plate I9 into said socket cylinder.

The plunger mechanism 36 comprises a cone- 'shaped outer shell 3|, an insulated cylinder 32, a cup member 33, and a movable plunger arm 34. The cone-shaped outer shell 3| has a lower flange which is attached to the circular outer plate I9 of socket cylinder I'Il by means of clamping screws 33. Insulated cylinder 32 is contained within cone-shaped shell 3|, being held in locked position between said cone-shaped shell and circular plate I9 by an integral annular flange or bead 31.

Cup member 33 is press-tted within insulated cylinder 32. The plunger arm 34 is slidably contained within said cup member 33, the same being held under spring tension in extended position by a return spring 38.

Plunger arm 34 is hollow, having a longitudinal bore or recess 39, the open end of which is inwardly threaded as at 40. Into the said threaded portion 46, the threaded portion of a closure member 4| is inserted, said closure member having a terminal ange 42 which abuts the The said l outer edge of the cup member 33 and prevents the plunger arm 34 from being removed from the assembly. A plunger head 43 is slidably set through the center of the closure member 4I, said plunger head 43 having a terminal flange 44 which ts within the -bore 39 of the plunger arm 34. The free end of the plunger head 43 carries an integral, mushroom-shaped contact head 45 which in normal position is centrally located within the socket cylinder forward of the base wall I4, and between the retaining arms 21. A return spring 46 is located within the bore 39 of arm 34, said spring extending between the lclosed end of said bore and the terminal flange 44 o f the plunger head 43. Spring 46 maintains said plunger head 43 in its normally extended position vshown in Fig. 2. When a bulb is inserted in the socket, however, the base of said bulb exerts a pressure upon the contact head 45, forcing the plunger head 43 inwardly against the tension of spring 46 to the position shown in broken lines in Fig. 2.

The outer'closed end of the plunger arm 34 carries a flanged portion 41, which is of suicient diameter to enable it to slide freely within the cup member 33. The return spring 38 is contained within the `cup member 33 and around the plunger arm 34, said spring 38 extending longitudinally between the flanged portion 41 of said plunger arm ad the closed end of the cup member 33. Said spring 38 maintains the plunger arm 34 in the extended position shown in Fig. 2 with the flanged portion 41 adjacent the outer open end of cup member 33.

An insulated finger-piece 49 is centrally positioned within the outer edge of the anged portion 41 of the plunger arm 34. Said nger piece 49 protrudes laterally outside the cup member 33 and provides the means whereby the user of the device may push the plunger arm 34 forwardly within the said cup member 33 against the tension of spring 38, as shown in Fig. 4.

That portion of the side wall I3 of socket cyl-v within the base cylinder |I adjacent opening 5|)v in such a position that the cut-away portion 52 extends through said opening 50. Lying adjacent the inner side of wall I3 and covering opening 50, is an insulated disc 53, above which a conductive disc 54 is located in parallel adjacent relation thereto. Disc 53 is positioned interme-fr diate disc 54 and block 5I. All said three members are secured together around ropening 50 by a clamping screw 55, which is made of a. conductive material. An insulated wire 56 is attached at one end to the conductive disc 54, and, passing through the base wall I4, the raised inner portion 23 of the circular plate I9, and the insulated cylinder 32, is connected at the other end to the cup member 33 adjacent the inner end thereof. The attachment of the wire 56 may be done by soldering or by any other convenient and suitable method.

The base cylinder II is threaded at its lower n the conductive disc 64 and thence through the insulated wire 56. The current will then flow through the cup member 33, through the plunger arm 34 and the spring 38, through the plunger head 43, the contact head 45 and finally through the base of the bulb (not shown) which abuts the contact head 45. To complete the circuit the current will ilow fr0m` the base of the bulb through the retaining arms 31, through the base wall I4 and along the walls of the socket cylinder I0 and base cylinder Il, until it reaches the battery casing.

In putting to usel the novel features of my device, the rotatable disc I1 is turned until the retaining arms 21 are brought approximately to their desired positions to conform to the size of the bulb base. The base of the flashlight bulb is then inserted between the flared upper ends 29 of the retaining arms 21, and the bulb is depressed until its base contacts the contact head 42 of the plunger arm 43. The purpose of the spring 46 now becomes apparent; said spring 45 enabling the contact head45 to abut the base of a flashlight bulb of any size.

It may be readily observed from an examination of the drawings that a bulb, once inserted between the four retaining arms 21, will be held in secured position by reason of the resilient and springy material from which said retaining arms 21 are constructed. Further, it is impossible for pressure upon the retaining arms to cause the rotatable disc i8 to rotate Clockwise and thus loosen the grip of said retaining arms upon the bulb base. This is due to the fact that any internal force on the retaining arms would cause the pins 26 to bear against the outer side edges of slots 23,

since the longitudinal axis of said slots 23 are substantially perpendicular to the line of movement of said pins 26. Thus, the retaining arms 21 can not be moved unless the disc I8 is rotated.

After the bulb has been ignited, and while it is still hot, the bulb may be ejected by the operation of the plunger mechanism 30. When the nger piece 49 is depressed, the plunger arm 34 is moved inwardly against the tension of the spring 48. against the. base of the bulb the plunger head 43 will be forced into the recess 39 in the plunger arm 34, until the said contact head 45 bears against the closure member 4l. At this point,

the said contact head 45 will be carried forwardly i with the plunger arm 34, pushing the base of the bulb forwardly until it clears the flared ends 29 of the retaining arms 21. The springs 38 and 43 will then return the aforementioned parts back to their normal position shown in Fig. 2.

While a preferred embodiment of my invention has been shown and described herein, it is obvious that numerous additions, changes, and omissions may be made in the invention without departing from the spirit and scope thereof.

I claim:

1. A socket for photographic flash-light bulbs comprising a socket shell, a disc mounted laterally and rotatably within said shell, said disc having a series of spaced slots formed therein, and a plurality of bulb-retaining arms pivotally attached to said shell, each of said arms having a depending pin, each of said pins extending into one of the slots in said disc, said slots being positioned to push said pins and to rotate said arms toward and away from the center of said socket shell when said disc is rotated.

2. A socket for photographic flash-light bulbs according to claim 1, in which a plunger assembly is mounted on the outside of said socket cylinder,

Since the Contact head 45 is resting flll said plunger assembly having a contact head which extends centrally within said socket cylinder and is positioned to normally contact the base of a bulb inserted between said bulb-retaining arms, and to push the bulb longitudinally out of contact with the bulb-retaining arms when said plunger assembly is operated.

3. A socket for photographic flash-light bulbs comprising a socket shell having an inner bottom wall and an outer bottom Wall, a disc rotatably and laterally mounted between said bottom walls, and a series of bulb-retaining arms pivotally attached to said inner bottom Wall, said inner bottom wall having a plurality of spaced, radiallyextending slots corresponding in number to said bulb-retaining arms, said disc having an equal number of spaced slots which register with the slots of the inner bottom wall at an angle thereto, each of said bulb-retaining arms carrying a depending pin, each of said pins extending through one of the slots of the inner bottom wall and into one of the slots of the disc, the slots of the disc being arranged to push the pins longitudinally within the slots of the inner bottom wall when said disc is rotated.

4. A socket for photographic Hash-light bulbs comprising a socket shell having an inner bottom wall and an outer bottom wall, a disc rotatably and laterally mounted between said bottom walls, and a series of bulb-retaining arms, each of said bulb-retaining arms comprising a flat base member pivotally mounted on the inner bottom wall in parallel relation thereto, and an upright, resilient retaining member xedly secured to the at base member adjacent the free end thereof, said inner bottom wall having a plurality of spaced, radially-extending slots corresponding in number to said bulb-retaining arms, said disc having an equal number of spaced slots which register with the slots of the inner bottom wall at an angle thereto, each of said at base members of said bulb retaining arms carrying a depending pln, each of said pins extending through one of the slots of the inner bottom Wall and into one of the slots of the disc, the slots of said disc being arranged to push said pin longitudinally within the slot of the inner bottom wall when said disc is rotated.

5. A socket for photographic flash-light bulbs comprising a socket shell having an inner bottom wall and an outer bottom wall, a disc rotatably and laterally mounted between said bottom walls, a plunger assembly located outside said socket shell and attached to said outer bottom wall, and a plurality of bulb-retaining arms, each of said bulb-retaining arms pivotally secured to the inner bottom wall, said inner bottom Wall having a plurality of spaced, radially-extending slots corresponding in number to said bulb-retaining arms, said disc having an equal number of spaced slots which register with the slots of the inner bottom wall at an angle thereto, each of said bulb-retaining arms carrying a depending pin, each of said pins extending through one of the slots of the inner bottom wall and into one of the slots of the disc, the slots of the disc being arranged to push the pins longitudinally within the slots of the inner bottom wall when said disc is rotated, the plunger element having a contact head which extends centrally within the socket shell between the said bulb-retaining arms, said contact head being spring-tensioned to bear against the base of a bulb retained between the said bulb-retaining arms, said plunger element being positioned to thrust the bulb longitudinally toward the open 8 epd ofl:ssidnsqclreiz-'ylinden mut of `Contact with UNITED STATES PATENTS said bulb-retaining arms;

z6. yA `socket iaccording torcla-im 5, in which the Number Name Date top, ends. of Ythe bulb-retaining. arms are out- 2,343,552 Hollister et al. Mar- '7J 1944 wardyyraredto "form a. lip, .sa'nidbulb-rftaning 5 FOREIGN PATENTS arms bemg also made of a reslhent material.

GUSTAV PRAGER.A Number Country Date 339 Great Britain 18.65 REFERENCES CITED The --fo'lluwing `references `are of record/in the 1 le'fof this patent: 

